Custom Gateway Plugin

Perhaps the following resources will help:

• https://docs.woocommerce.com/document/payment-gateway-api/
• https://www.skyverge.com/blog/how-to-create-a-simple-woocommerce-payment-gateway/
• https://www.ibenic.com/how-to-create-a-custom-woocommerce-payment-gateway/
• https://www.sitepoint.com/building-a-woocommerce-payment-extension/

1) Depends on the gateway you’re trying to build it for; This will be supplied by the gateway.
2) Depends on the response sent (if any);
3) See resources above.

Thanks Riaan for the answer,

very helpful links, but i still need to understand one thing, the gateway i’m using is Form-based so i need to call a URL where i send some required data (merchant ID, security hashs, …) along with the total amount to be paid this would open a new tab in the browser than it should get me back to woo where i should verify the payment so it’s pretty like Paypal

but with paypal there’s an SDK to use
if i don’t have an SDK how do i invoke the URL call and when i get back using the callback url i’m being redirected to a thank you page how i should verify the payment

thanks in advance